1. Field of the Invention
The present invention relates generally to orthopedic braces and, in particular, to orthopedic knee braces.
2. Description of the Related Art
Osteoarthritis is a degenerative joint disease that results in chronic pain in an affected joint when the joint is statically or dynamically loaded. In an affected knee joint, osteoarthritis pain is often caused by an unbalanced loading on the medial or lateral compartment of the knee, which can reduce the clearance space between the condyles of the femur and tibial plateau. When there is increased pressure between the femoral and tibial surfaces in an affected compartment of the knee joint, and particularly dynamic pressure, cartilage degeneration can occur at the contact surface producing pain in the joint.
Orthopedic knee braces are commonly applied to the leg to treat osteoarthritis in the knee. Such braces typically include an upper support portion for securing to the upper leg of the wearer, a lower support portion for securing to the lower leg, and one or more hinge assemblies pivotally interconnecting the upper and lower support portions. In a two-sided knee brace, a hinge assembly is located at each side of the knee when the brace is worn. A condyle pad is typically located between each hinge assembly and side of the knee.
Knee braces of the type described serve to reduce osteoarthritis pain in the knee joint by applying a three-point load to the leg. A force is applied to the side of the knee opposite the affected compartment by causing the adjacent condyle pad to forcibly contact the side of the knee. This is typically accomplished by increasing the thickness of the adjacent condyle pad or by moving the pad closer to the knee using a jackscrew or other means. Alternatively, a force is sometimes applied opposite the affected compartment of the knee by means of an adjustable force strap which extends around the leg in a helical fashion from the upper support portion to the lower support portion. In either case, counteracting forces are applied to the leg in the medial/lateral plane above and below the knee on the side of the affected compartment by the upper and lower support portions. The resulting three-point load on the leg serves to reduce osteoarthritis pain in the knee joint by reducing the load in the affected compartment of the knee.
While such knee braces have proven effective in relieving osteoarthritis pain in the knee joint, the upper and lower support portions of such braces lack sufficient adjustability for optimal fit on various leg shapes and for various loads to relieve osteoarthritis pain. The upper and lower support portions are typically relatively rigid and are not adapted to conform to the leg shape of the wearer. As a result, such braces are often bulky, uncomfortable, and ill-fitting. In addition, when such braces are adjusted to apply a force to the knee or to fit the leg of a patient, stress is generated in the hinge assemblies of the knee braces. This stress causes wear on the components of the hinge assemblies and, in extreme cases, can result in binding of the hinge assemblies.